Kinetic properties of the alloy NiMn in the B2 phase

The electron energy spectrum of the B2 phase of NiMn was calculated by the nonself-consistent MI KKP method. Calculations were carried out for the electronic density of states, the cross sections of the Fermi surface, and the temperature dependences of the resistivity and the thermoelectromotive force S. Experimental measurements were made of and S in the region of existence of the B2 phase. Satisfactory agreement was obtained between the calculated dependences of and S and the experimental data.Translated from Izvestiya Vysshikh Uchebnykh Zavedenii, Fizika, No. 10, pp. 23–26, October, 1981.The authors are grateful to I. N. Fedyainova for assistance in calculating the kinetic coefficients.     

Phase transitions in zirconium dioxide powder after being subjected to impulsive loads

We study the structure of zirconium dioxide powder, initially in tetragonal form, subjected to shock waves up to 43 MPa in amplitude. It is shown that after shock-wave loading a complicated structure is formed with monoclinic and x-ray-amorphous phases. The amount of the monoclinic phase reaches a maximum at a pressure of 10 GPa, while the amount of the x-ray-amorphous phase increases monotonically with increasing pressure. It is shown that the x-ray-amorphous phase results from mixing of different polytypes after shock waves pass through the material.Translated from Izvestiya Vysshikh Uchebnykh Zavedenii, Fizika, No. 1, pp. 51–55, January, 1995.     

Deformation processes in tungsten carbide powder ground in a ball mill

Electron diffraction microscopy and x-ray structural analysis are used to study the evolution of particle size and defect structure in tungsten carbide powder during deformation by grinding in a ball mill. Correlations are obtained between grinding time, particle size, and defect structure parameters (scalar dislocation density and azimuthal component of the full disorientation angle).Structural Engineering Institute, Institute of Strength Physics and Materials Science, Siberian Branch, Russian Academy of Sciences. Translated from Izvestiya Vysshikh Uchebnykh Zavedenii, Fizika, No. 5, pp. 62–67, May, 1992.     

In situ X-ray investigation of deformation martensite in titanium nickelide

X-ray structural analysis was used to carry out an investigation of the martensitic transformation in titanium nickelide during mechanical loading. A diffractometer with filtered cobalt radiation was used, along with an attachment that allowed the sample to be loaded by bending. No R-martensite was observed during loading. The structure of deformation martensite was identified as monoclinic B19. When deformation is increased, the martensite has a more complicated structure and was identified as a mixture of monoclinic B19 and triclinic B19 phases. When the load is removed, the triclinic martensite disappears without hysteresis, whereas a small amount of monoclinic martensite remains and disappears only when heated to 40–60C.Translated from Izvestiya Vysshikh Uchebnykh Zavedenii, Fizika, No. 5, pp. 39–41, May, 1991.     

Structural-phase changes in hard alloy WC-steel 110G13 after dynamic loading

The methods of optical and electron diffraction microscopy are used to study the evolution of phase composition and defect structure in hard alloy WC-steel 100G13 after dynamic loading. Both stable and metastable austenite (the binding phase) are seen in the alloy after such loading. The martensitic transformation is seen along with slip in the case of the metastable state, which makes it possible to significantly reduce the scale of plastic deformation of the binder and redistribute the external load onto particles of the reinforcing phase. Microcracks form a special structure in this case, and the integrity of the specimen is maintained up to high loading rates.Institute of the Strength Physics and Materials Science, Siberian Department of the Russian Academy of Sciences. Translated from Izvestiya Vysshikh Uchebnykh Zavedenii, Fizika, No. 8, pp. 68–72, August, 1994.     

Study of the Microstructure and Phase-Composition of a WC-Alloy with a Hadfield Steel Binder

The phase composition and structure of a tungsten carbide alloy with a Hadfield steel binder are studied using metallography, x-ray diffraction analysis, and transmission electron microscopy. It is found that tungsten carbide is dissolved in the binder during sintering. This gives rise to a nonuniform distribution of the alloying additions in the -solid solution, which results in precipitation of complex carbides of the (W, Fe) _x C type having different crystal-lattice parameters. The volume fraction of these carbides is as high as 9–10%.     

Structural changes in TiC-TiNi alloys on deformation

The deformation of a composition material with a binding phase of shearing-unstable alloy, namely, titanium nickelide, is considered. X-ray structural analysis and electron—positron annihilation methods are used to investigate the structural changes in the composite material as a function of the degree of deformation. It is shown that the deformation produces the structural phase transition B2 B19, which is confirmed by x-ray structural investigations and electron positron annihilation.Institute of Strength Physics and Materials Science, Siberian Branch, Russian Academy of Sciences. Translated from Izvestiya Uchebnykh Zavednii, Fizika, No. 4, pp. 100–103, April, 1994.     

Structural-phase analysis of sintered alloy WC-30% steel 110G13

Electron diffraction microscopy and x-ray diffraction analysis are used to study the phase composition and structure of hard alloy WC-steel 110G13 immediately after sintering and additional heat treatment. It is shown that quenching in water from 1370 K leads to disappearance of the excess phases and the formation of a less defective and more uniform structure.Institute of Strength Physics and Materials Science, Siberian Branch of the Russian Academy of Sciences. Tomsk State Architectural-Construction Academy. Translated from Izvestiya Vysshikh Uchebnykh Zavedenii, Fizika, No. 5, pp. 96–99, May, 1993.